What happened
On August 10, 2010, a Cessna F152 was on a VFR approach to Winzeln-Schramberg airfield after departing from Neuhausen ob Eck. The pilot had previously coordinated the landing with the airfield contact via telephone. As the aircraft approached runway 33, the pilot received landing clearance at his own discretion from the airfield controller.
Simultaneously, a DG 30 and glider was performing a long landing on the same runway. The glider pilot had notified the airfield of his intention for a long landing, but this message was not acknowledged by the controller. While the glider pilot initially saw the Cessna, the two aircraft subsequently lost visual contact with one another.
As the aircraft approached the runway threshold, the airfield controller issued a command for the Cessna to perform a go-around. The pilot of the Cessna attempted to maintain altitude during the maneuver. However, due to the higher approach speed of the powered aircraft and the lack of mutual visibility, the Cessna F152 collided with the glider from above at an altitude of approximately 40 meters. Both aircraft sustained heavy damage, but there were no fatalities or injuries.
The investigation
The BFU investigation utilized GPS flight data from both aircraft to reconstruct the flight paths. The analysis revealed that while the aircraft were initially separated by approximately 500 meters horizontally and 50 meters vertically, they closed the distance to within 120 meters horizontally and 70 meters vertically without the pilots seeing each other. The investigation also examined radio communications between the pilots and the airfield controller, as well as the glider pilot's maneuvers, which included crossing the runway centerline twice while attempting to adjust his landing position.
Findings
- The primary cause of the accident was the unnoticed approach of both aircraft during the final phase of the landing.
- Inadequate communication between the airfield controller and the approaching aircraft contributed to the situation, as the controller identified the conflict too late.
- The glider pilot's maneuvers, which involved crossing the runway centerline twice to reach a different landing area, complicated the traffic situation.
- The Cessna pilot's inability to see the glider was due to the high-wing configuration of the aircraft and the close vertical proximity of the glider.